1. Field of the Invention
The present invention relates to a liquid crystal display and a panel therefor.
2. Description of the Related Art
A liquid crystal display (LCD) is one of the most widely used flat panel displays. LCDs are used in notebook or laptop computers, desktop computer monitors and televisions. LCDs are lightweight and occupy less space than conventional cathode ray tube (CRT) displays.
An LCD generally includes a liquid crystal (LC) layer that is interposed between a pair of panels including field-generating electrodes such as pixel electrodes and a common electrode. The LC layer is subjected to an electric field generated by the field-generating electrodes and variations in the field strength change the molecular orientation of the LC layer. For example, upon application of an electric field, the molecules of the LC layer change their orientation to change polarization of incident light. Appropriately arranged polarizers partially or fully block the light, creating gray or dark areas that can represent desired images.
One measure of LCD quality is a standard viewing angle that is defined as a viewing angle giving a predetermined contrast ratio. Various techniques for enlarging the standard viewing angle have been suggested, including a technique utilizing a vertically aligned LC layer and providing cutouts or protrusions at pixel electrodes. The cutouts or the protrusions cause horizontal components in the electric field or pretilt in the LC molecules, which can determine tilt directions of the LC molecules, or and thus appropriately arranged cutouts or protrusions give various tilt directions to the LC molecules, thereby increasing the standard viewing angle.
However, the above-described LCD has a poor response time. Although the LC molecules near the cutouts or protrusions rapidly tilt in a direction in response to a strong horizontal component of the electric field, the LC molecules far from the cutouts or protrusions may experience a weak horizontal component and may not rapidly determine their tilt directions. As a result, the LC molecules far from the cutouts or protrusions may be tilted by push or collision by adjacent molecules.
The response time may be improved by making the distance between the cutouts or the protrusions.
However, the cutouts and the protrusions reduce the aperture ratio, and the aperture ratio is further decreased by approaching the cutouts or the protrusions. To increase aperture ratio, it has been suggested that the size of the pixel electrodes be maximized. However, maximization of the size of the pixel electrodes results in a close distance between the pixel electrodes, causing strong lateral electric fields between the pixel electrodes. The strong electric fields cause unwanted altering of the orientation of the LC molecules, yielding textures and light leakage and deteriorating display characteristics.